Monday–Friday, March 5–9, 2018;
Los Angeles, California

Abstract: P58.00003 : A biophysical model for the formation of mitotic spindle bipolarity*

3:42 PM–4:18 PM

Abstract

Presenter:

Robert Blackwell(Physics, University of Erlangen-Nürnberg)

Author:

Robert Blackwell(Physics, University of Erlangen-Nürnberg)

Mitotic spindles use an elegant bipolar architecture to segregate duplicated chromosomes with high fidelity. Bipolar spindles form from a monopolar initial condition; this is the most fundamental construction problem that the spindle must solve. Microtubules, motors, and cross-linkers are important for bipolarity, but the mechanisms necessary and sufficient for spindle assembly remain unknown.

By varying the features of our model, we identify a set of functions essential for the generation and stability of spindle bipolarity. When kinesin-5 motors are present, their bidirectionality is essential, but spindles can form in the presence of passive cross-linkers alone. We also identify characteristic failed states of spindle assembly—the persistent monopole, X spindle, separated asters, and short spindle, which are avoided by the creation and maintenance of antiparallel microtubule overlaps. More recently, we have begun to investigate the mechanisms responsible for chromosome bi-orientation, correction of kinetochore-microtubule attachment errors, and lost kinetochore capture.

*This work was funded by NSF grants DMR-0847685, DMR-1551095, and DMR-1420736; NIH grants K25GM110486, R01GM104976, and R01GM033787; a NIST/JILA-BioFrontiers seed grant; and a fellowship provided by matching funds from the NIH/University of Colorado Biophysics Training Program. The use of the Janus superc